Combine all marinating, add tri tip and let marinate 24 hours. Remove Tri Tip and reserve marinade. Cryovac tri tip, seal properly. Sous vide for 90 minutes at 136 degrees.
For Kabocha Puree:
Clean pumpkin, season with olive oil, salt & pepper, and roast for 45 minutes. Puree roasted pumpkin withh remaining ingredients. Season to taste.
For Tri Tip Sauce:
Heat Marinade and veal stock, reduce by 1/2. Finish sauce with butter and season to taste.
For Tartar Sauce:
Combine all ingredients and mix well
For Tempura Oysters:
Combine flour, eggs and iced water, mix well. Dust oysters with flour, dip in batter and coat with panko. Fry oysters till golden brown, season to taste.
Smear plate with pumpkin puree, place sauteed choi sum over puree. Re-heat and slice Tri Tip, place on top of Choi Sum and sauce. Place dollop of remoulade on plate, arrange fried oysters over sauce. Garnish tri tip with radish curls and micro greens.